package com.jsql.view.swing.table;
   
   import javax.swing.*;
   import javax.swing.event.ChangeEvent;
   import javax.swing.event.ChangeListener;
   import javax.swing.table.DefaultTableModel;
   import javax.swing.table.TableColumn;
   import javax.swing.table.TableColumnModel;
   import java.beans.PropertyChangeEvent;
  import java.beans.PropertyChangeListener;
  
  /**
   *  Prevent the specified number of columns from scrolling horizontally in
   *  the scroll pane. The table must already exist in the scroll pane.
   *
   *  The functionality is accomplished by creating a second JTable (fixed)
   *  that will share the TableModel and SelectionModel of the main table.
   *  This table will be used as the row header of the scroll pane.
   *
   *  The fixed table created can be accessed by using the getFixedTable()
   *  method. will be returned from this method. It will allow you to:
   *
   *  You can change the model of the main table and the change will be
   *  reflected in the fixed model. However, you cannot change the structure
   *  of the model.
   */
  public class FixedColumnTable implements ChangeListener, PropertyChangeListener {
      
      private JTable mainTable;
      private JTable fixedTable;
      private JScrollPane scrollPane;
  
      /**
       *  Specify the number of columns to be fixed and the scroll pane
       *  containing the table.
       */
      public void fixColumnSize(int fixedColumns, JScrollPane scrollPane) {
          this.scrollPane = scrollPane;
  
          this.mainTable = (JTable) scrollPane.getViewport().getView();
          this.mainTable.setAutoCreateColumnsFromModel(false);
          this.mainTable.addPropertyChangeListener(this);
  
          //  Use the existing table to create a new table sharing
          //  the DataModel and ListSelectionModel
          this.fixedTable = new JTable() {
              @Override
              public boolean isCellEditable(int row,int column) {
                  return false;
              }
          };
          
          this.fixedTable.setAutoCreateColumnsFromModel(false);
          
          final DefaultTableModel modelFixedTable = new DefaultTableModel() {
              @Override
              public int getColumnCount() {
                  return 2;
              }
              @Override
              public boolean isCellEditable(int row, int col) {
                  return false;
              }
              @Override
              public int getRowCount() {
                  return FixedColumnTable.this.mainTable.getRowCount();
              }
              @Override
              public Class<?> getColumnClass(int colNum) {
                  Class<?> columnClass;
                  if (colNum == 0) {
                      columnClass = String.class;
                  } else {
                      columnClass = super.getColumnClass(colNum);
                  }
                  return columnClass;
              }
          };
          
          this.fixedTable.setModel(modelFixedTable);
          this.fixedTable.setSelectionModel(this.mainTable.getSelectionModel());
          
          this.fixedTable.setRowHeight(20);
          this.fixedTable.setFocusable(false);
          this.fixedTable.getTableHeader().setReorderingAllowed(false);
          
          //  Remove the fixed columns from the main table
          //  and add them to the fixed table
          TableColumnModel columnModel = this.mainTable.getColumnModel();
          for (var i = 0 ; i < fixedColumns ; i++) {
              TableColumn column = columnModel.getColumn(i);
              column.setMinWidth(0);
              column.setMaxWidth(0);
              this.fixedTable.getColumnModel().addColumn(new TableColumn(i));
          }
  
          this.fixedTable.getColumnModel().getColumn(0).setCellRenderer(new RowHeaderRenderer());
          this.fixedTable.getColumnModel().getColumn(0).setResizable(false);
          this.fixedTable.getColumnModel().getColumn(0).setPreferredWidth(38);
         this.fixedTable.getColumnModel().getColumn(1).setCellRenderer(new RowHeaderRenderer());
         this.fixedTable.getColumnModel().getColumn(1).setResizable(false);
         this.fixedTable.getColumnModel().getColumn(1).setPreferredWidth(38);
 
         this.mainTable.getRowSorter().addRowSorterListener(rowSorterEvent -> {
             modelFixedTable.fireTableDataChanged();
             // Copy data from hidden column in main table
             for (var i = 0; i < this.mainTable.getRowCount() ; i++) {
                 this.fixedTable.setValueAt(this.mainTable.getValueAt(i, 0), i, 0);
                 this.fixedTable.setValueAt(this.mainTable.getValueAt(i, 1), i, 1);
             }
         });
         
         this.mainTable.getSelectionModel().addListSelectionListener(listSelectionEvent ->
             modelFixedTable.fireTableRowsUpdated(0, modelFixedTable.getRowCount() - 1)
         );
         
         // Copy data from first column of main table to fixed column
         for (var i = 0 ; i < this.mainTable.getRowCount() ; i++) {
             this.fixedTable.setValueAt(this.mainTable.getValueAt(i, 0), i, 0);
             this.fixedTable.setValueAt(this.mainTable.getValueAt(i, 1), i, 1);
         }
         
         //  Add the fixed table to the scroll pane
         this.fixedTable.setPreferredScrollableViewportSize(this.fixedTable.getPreferredSize());
         scrollPane.setRowHeaderView(this.fixedTable);
         scrollPane.setCorner(ScrollPaneConstants.UPPER_LEFT_CORNER, this.fixedTable.getTableHeader());
 
         // Synchronize scrolling of the row header with the main table
         scrollPane.getRowHeader().addChangeListener(this);
     }
 
     /**
      * Implement the ChangeListener
      */
     @Override
     public void stateChanged(ChangeEvent e) {
         //  Sync the scroll pane scrollbar with the row header
         JViewport viewport = (JViewport) e.getSource();
         this.scrollPane.getVerticalScrollBar().setValue(viewport.getViewPosition().y);
     }
     
     /**
      * Implement the PropertyChangeListener
      */
     @Override
     public void propertyChange(PropertyChangeEvent e) {
         //  Keep the fixed table in sync with the main table
         if ("selectionModel".equals(e.getPropertyName())) {
             this.fixedTable.setSelectionModel(this.mainTable.getSelectionModel());
         }
 
         if ("model".equals(e.getPropertyName())) {
             this.fixedTable.setModel(this.mainTable.getModel());
         }
     }
 }